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460 BCE
Democrituts
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John Dalton
John Dalton was an English chemist. That discovered the atomic theory. Where everything is made with atoms. An atom is made up of protons, neutrons, and electrons. It is impossible to break an atom. It s an invisble tiny particle called atom. Also there are formulas he created. He is best known for his pioneering work in the development of modern atomic theory; and his research into color blindness, sometimes referred to as Daltonism, in his honor. https://www.youtube.com/watch?v=OUoV--CuLDA -
J. J. Thompson
Sir Joseph John Thomson OM PRS was an English physicist. He was elected as a fellow of the Royal Society of London and appointed to the Cavendish Professorship of Experimental Physics at the Cambridge University's Cavendish Laboratory in 1884. He discovered the electron when he was experimenting with gas discharge tubes. He also knew that electrons are negative charged. http://study.com/academy/lesson/jj-thomsons-cathode-ray-tube-crt-definition-experiment-diagram.html -
Lord Ernest Rutherford
Ernest Rutherford conducted a experiment the gold foil. He used alpha particles. He is experiments the particles, they reflect back some stay. So this was his discovery. Also he used positively charged particles. This experiment got him famous. https://www.youtube.com/watch?v=XBqHkraf8iE -
Niels Bohr
